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I • 2005 AHR McClane ~ Munger Canyon Mines Page 5 <br />Groundwater <br />Table 5 shows the results of groundwater sampling during the water year. Baseline <br />data from the 1981 & 1986 monitoring is also shown. Results of quality sampling are <br />consistent with the results from previous years. GW-4 in close proximity to a hay field <br />that is irrigated during dry periods and in danger of being eroded with an oxbow has <br />been replaced with GW-3. GW-3 is located adjacent to the road south of GW-4 and <br />should be outside of the influence of the irrigation of the hay field. Refer to Figure 4.2-2 <br />of the McClane Canyon Permit. The Division of Minerals & Geology has approved this <br />substitution. <br />_ Pond Discharges _ <br />There was one discharge from each of the Munger and McClane sediment ponds <br />during the water year. The sediment fences at McClane, Munger Canyon and Loma <br />were maintained as necessary. <br />Discharge monitoring from the sediment ponds and mines are regulated by the Colorado <br />Discharge Permit System Numbers CO-0038342 (McClane) and CO-0040827 (Munger). <br />Copies of Quarterly Discharge Monitoring Reports have been provided, under separate <br />cover, to the DMG at the same schedule required by the CDPS Permit. They are included <br />• in this report by reference. During August 2005, CAM was issued a Permit Effluence <br />Violation for ouffall number 002A at McClane Canyon, for Total Suspended Solids (TSS). <br />Acceptable TSS levels are 35, and the reading was 70. Outtall 002A provides for <br />discharge from the underground mine to East Salt Creek. Water is pumped from the active <br />mine workings to a nearby sump and then settled prior to discharge. From the nearby <br />active sumps, water is transferred to the finishing mine sump and then is pumped from the <br />finishing mine sump to Outfall 002A. The steps to be taken to regain and maintain <br />compliance with permit conditions are as follows: 1) The finishing sump will be filled to <br />capacity during the last shifts of the week, 2) The water in the finishing sump will be <br />allowed to settle over the weekend, and 3) Water will be discharged from the finishing <br />sump early in the week, prior to any water transfer from the active mine sumps. <br />McClane Creek Temporary Diversion <br />The Operator placed four wooden gabions in the McClane Creek channel during 1997 <br />to ensure the channel would remain stable. The gabions were to provide a solid place <br />in the channel bottom to limit any further erosion. In 2004 a re-survey was conducted <br />and the data and inspection observations show there has been significant erosion <br />subsequent to the 1997 gabion installation. Future high flow events may result in <br />additional channel scour and side-cutting erosion. Portions of the diverted channel <br />appeared to be unstable and further erosion may be likely. The most effective long <br />term solution to the erosion problem was determined to be restoring McClane Creek to <br />it's original flow configuration. Therefore, the operator plans to install a 48" culvert ("P") <br />under the haul road in order to reconnect upper McClane Creek to it's original lower <br />• segment. Culvert "P" should be installed during the next reporting period. <br />Amended 6I1I06 <br />